65440231 has 4 divisors (see below), whose sum is σ = 65477952. Its totient is φ = 65402512.

The previous prime is 65440201. The next prime is 65440247. The reversal of 65440231 is 13204456.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 65440231 - 2⁷ = 65440103 is a prime.

It is a super-2 number, since 2×65440231² = 8564847666666722, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 65440196 and 65440205.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (65440201) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 16126 + ... + 19771.

It is an arithmetic number, because the mean of its divisors is an integer number (16369488).

Almost surely, 2^65440231 is an apocalyptic number.

65440231 is a deficient number, since it is larger than the sum of its proper divisors (37721).

65440231 is a wasteful number, since it uses less digits than its factorization.

65440231 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 37720.

The product of its (nonzero) digits is 2880, while the sum is 25.

The square root of 65440231 is about 8089.5136442187. The cubic root of 65440231 is about 402.9782512631.

Adding to 65440231 its reverse (13204456), we get a palindrome (78644687).

The spelling of 65440231 in words is "sixty-five million, four hundred forty thousand, two hundred thirty-one".